Drug information of Polymyxin b sulfate

Polymyxin b sulfate

Drug group:

Polymyxin b sulfate is a polypeptide antibiotic. It works by killing sensitive bacteria. To reduce the development of drug-resistant bacteria and maintain the effectiveness of polymyxin B and other antibacterial drugs, polymyxin B should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

Mechanism of effect

Polymyxin B sulfate has a bactericidal action against almost all gram-negative bacilli except theProteus group. Polymyxins increase the permeability of the bacterial cell membrane leading to death of the cell.


Polymyxin B is used for infections with gram-negative organisms


Polymyxin B sulfate is not absorbed from the normal alimentary tract. The drug is excreted slowly by the kidneys. Tissue diffusion is poor and the drug does not pass the blood brain barrier into the cerebrospinal fluid.


Intravenous Dissolve 500,000 polymyxin B units in 300 to 500 mL solutions for parenteral dextrose injection 5% for continuous drip. Adults and children: 15,000 to 25,000 units/kg body weight/day in individuals with normal kidney function. This amount should be reduced from 15,000 units/kg downward for individuals with kidney impairment. Infusions may be given every 12 hours; however, the total daily dose must not exceed 25,000 units/kg/day. Infants: Infants with normal kidney function may receive up to 40,000 units/kg/day without adverse effects Ophthalmic: Dissolve 500,000 polymyxin B units in 20 to 50 mL sterile water for injection or sodium chloride injection USP for a 10,000 to 25,000 units per mL concentration. For the treatment of P. aeruginosa infections of the eye, a concentration of 0.1 percent to 0.25 percent (10,000 units to 25,000 units per mL) is administered 1 to 3 drops every hour, increasing the intervals as response indicates. Note: Avoid total systemic and ophthalmic instillation over 25,000 units/kg/day.


1-Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Polymyxin B for Injection, and may range in severity from mild diarrhea to fatal colitis. 2-Avoid concurrent use of a curariform muscle relaxant and other neurotoxic drugs (ether, tubocurarine, succinylcholine, gallamine, decamethonium and sodium citrate) which may precipitate respiratory depression. If signs of respiratory paralysis appear, respiration should be assisted as required, and the drug discontinued.

Points of recommendation

1-Patients should be counseled that antibacterial drugs including polymyxin B should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). 2-patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed.

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